Spaces:
Sleeping
Sleeping
File size: 8,213 Bytes
6219ec9 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 |
"""distutils.file_util
Utility functions for operating on single files.
"""
import os
from .errors import DistutilsFileError
from ._log import log
# for generating verbose output in 'copy_file()'
_copy_action = {None: 'copying', 'hard': 'hard linking', 'sym': 'symbolically linking'}
def _copy_file_contents(src, dst, buffer_size=16 * 1024): # noqa: C901
"""Copy the file 'src' to 'dst'; both must be filenames. Any error
opening either file, reading from 'src', or writing to 'dst', raises
DistutilsFileError. Data is read/written in chunks of 'buffer_size'
bytes (default 16k). No attempt is made to handle anything apart from
regular files.
"""
# Stolen from shutil module in the standard library, but with
# custom error-handling added.
fsrc = None
fdst = None
try:
try:
fsrc = open(src, 'rb')
except OSError as e:
raise DistutilsFileError("could not open '{}': {}".format(src, e.strerror))
if os.path.exists(dst):
try:
os.unlink(dst)
except OSError as e:
raise DistutilsFileError(
"could not delete '{}': {}".format(dst, e.strerror)
)
try:
fdst = open(dst, 'wb')
except OSError as e:
raise DistutilsFileError(
"could not create '{}': {}".format(dst, e.strerror)
)
while True:
try:
buf = fsrc.read(buffer_size)
except OSError as e:
raise DistutilsFileError(
"could not read from '{}': {}".format(src, e.strerror)
)
if not buf:
break
try:
fdst.write(buf)
except OSError as e:
raise DistutilsFileError(
"could not write to '{}': {}".format(dst, e.strerror)
)
finally:
if fdst:
fdst.close()
if fsrc:
fsrc.close()
def copy_file( # noqa: C901
src,
dst,
preserve_mode=1,
preserve_times=1,
update=0,
link=None,
verbose=1,
dry_run=0,
):
"""Copy a file 'src' to 'dst'. If 'dst' is a directory, then 'src' is
copied there with the same name; otherwise, it must be a filename. (If
the file exists, it will be ruthlessly clobbered.) If 'preserve_mode'
is true (the default), the file's mode (type and permission bits, or
whatever is analogous on the current platform) is copied. If
'preserve_times' is true (the default), the last-modified and
last-access times are copied as well. If 'update' is true, 'src' will
only be copied if 'dst' does not exist, or if 'dst' does exist but is
older than 'src'.
'link' allows you to make hard links (os.link) or symbolic links
(os.symlink) instead of copying: set it to "hard" or "sym"; if it is
None (the default), files are copied. Don't set 'link' on systems that
don't support it: 'copy_file()' doesn't check if hard or symbolic
linking is available. If hardlink fails, falls back to
_copy_file_contents().
Under Mac OS, uses the native file copy function in macostools; on
other systems, uses '_copy_file_contents()' to copy file contents.
Return a tuple (dest_name, copied): 'dest_name' is the actual name of
the output file, and 'copied' is true if the file was copied (or would
have been copied, if 'dry_run' true).
"""
# XXX if the destination file already exists, we clobber it if
# copying, but blow up if linking. Hmmm. And I don't know what
# macostools.copyfile() does. Should definitely be consistent, and
# should probably blow up if destination exists and we would be
# changing it (ie. it's not already a hard/soft link to src OR
# (not update) and (src newer than dst).
from distutils.dep_util import newer
from stat import ST_ATIME, ST_MTIME, ST_MODE, S_IMODE
if not os.path.isfile(src):
raise DistutilsFileError(
"can't copy '%s': doesn't exist or not a regular file" % src
)
if os.path.isdir(dst):
dir = dst
dst = os.path.join(dst, os.path.basename(src))
else:
dir = os.path.dirname(dst)
if update and not newer(src, dst):
if verbose >= 1:
log.debug("not copying %s (output up-to-date)", src)
return (dst, 0)
try:
action = _copy_action[link]
except KeyError:
raise ValueError("invalid value '%s' for 'link' argument" % link)
if verbose >= 1:
if os.path.basename(dst) == os.path.basename(src):
log.info("%s %s -> %s", action, src, dir)
else:
log.info("%s %s -> %s", action, src, dst)
if dry_run:
return (dst, 1)
# If linking (hard or symbolic), use the appropriate system call
# (Unix only, of course, but that's the caller's responsibility)
elif link == 'hard':
if not (os.path.exists(dst) and os.path.samefile(src, dst)):
try:
os.link(src, dst)
return (dst, 1)
except OSError:
# If hard linking fails, fall back on copying file
# (some special filesystems don't support hard linking
# even under Unix, see issue #8876).
pass
elif link == 'sym':
if not (os.path.exists(dst) and os.path.samefile(src, dst)):
os.symlink(src, dst)
return (dst, 1)
# Otherwise (non-Mac, not linking), copy the file contents and
# (optionally) copy the times and mode.
_copy_file_contents(src, dst)
if preserve_mode or preserve_times:
st = os.stat(src)
# According to David Ascher <da@ski.org>, utime() should be done
# before chmod() (at least under NT).
if preserve_times:
os.utime(dst, (st[ST_ATIME], st[ST_MTIME]))
if preserve_mode:
os.chmod(dst, S_IMODE(st[ST_MODE]))
return (dst, 1)
# XXX I suspect this is Unix-specific -- need porting help!
def move_file(src, dst, verbose=1, dry_run=0): # noqa: C901
"""Move a file 'src' to 'dst'. If 'dst' is a directory, the file will
be moved into it with the same name; otherwise, 'src' is just renamed
to 'dst'. Return the new full name of the file.
Handles cross-device moves on Unix using 'copy_file()'. What about
other systems???
"""
from os.path import exists, isfile, isdir, basename, dirname
import errno
if verbose >= 1:
log.info("moving %s -> %s", src, dst)
if dry_run:
return dst
if not isfile(src):
raise DistutilsFileError("can't move '%s': not a regular file" % src)
if isdir(dst):
dst = os.path.join(dst, basename(src))
elif exists(dst):
raise DistutilsFileError(
"can't move '{}': destination '{}' already exists".format(src, dst)
)
if not isdir(dirname(dst)):
raise DistutilsFileError(
"can't move '{}': destination '{}' not a valid path".format(src, dst)
)
copy_it = False
try:
os.rename(src, dst)
except OSError as e:
(num, msg) = e.args
if num == errno.EXDEV:
copy_it = True
else:
raise DistutilsFileError(
"couldn't move '{}' to '{}': {}".format(src, dst, msg)
)
if copy_it:
copy_file(src, dst, verbose=verbose)
try:
os.unlink(src)
except OSError as e:
(num, msg) = e.args
try:
os.unlink(dst)
except OSError:
pass
raise DistutilsFileError(
"couldn't move '%s' to '%s' by copy/delete: "
"delete '%s' failed: %s" % (src, dst, src, msg)
)
return dst
def write_file(filename, contents):
"""Create a file with the specified name and write 'contents' (a
sequence of strings without line terminators) to it.
"""
f = open(filename, "w")
try:
for line in contents:
f.write(line + "\n")
finally:
f.close()
|